Reconn's World Forum http://www.reconnsworld.com/forum/index.php Thu, 17 May 2012 01:53:59 -0700 Phorum 5.2.9a http://www.reconnsworld.com/forum/read.php?7,529,529#msg-529 I want to do at the beginning of each hour with a blown LED. Please HELP (no replies) http://www.reconnsworld.com/forum/read.php?7,529,529#msg-529 .Me e-mail: emirkutlay@hotmail.com]]> guest LED's Sun, 16 Oct 2011 13:54:42 -0700 http://www.reconnsworld.com/forum/read.php?14,525,525#msg-525 Amplifier Circuit (no replies) http://www.reconnsworld.com/forum/read.php?14,525,525#msg-525 Can anybody help me please? I need an Amplifier circuit (LM741cn) which uses 3 potentiometers as Bass Treble and Volume. I am really struggling to create it. I realised that i can put an alternating resistor in to help with the volume control. And 4 capacitors for the AC. Look forward to replys!!! Thank You]]> guest Battery Power Monitors Mon, 16 May 2011 06:42:33 -0700 http://www.reconnsworld.com/forum/read.php?37,523,523#msg-523 Voltage comparator help needed for a newbie (no replies) http://www.reconnsworld.com/forum/read.php?37,523,523#msg-523 guest E-mail Bag Thu, 02 Dec 2010 02:23:48 -0800 http://www.reconnsworld.com/forum/read.php?26,521,521#msg-521 mic amplifier (no replies) http://www.reconnsworld.com/forum/read.php?26,521,521#msg-521
Phil]]> guest Comments, Suggestions, Conversation Sat, 08 May 2010 12:51:12 -0700 http://www.reconnsworld.com/forum/read.php?37,514,514#msg-514 Pressure Switch info (no replies) http://www.reconnsworld.com/forum/read.php?37,514,514#msg-514
(Please reply to: phillipv at nb.sympatico.ca)

I need to identify some sort of pressure sensor(s) with which to be placed at specific anatomical read-points along the Exo-frame:

1. Inner wrist for biceps contraction
2. Outer wrist for triceps contraction
3. Mid-biceps for shoulder raise
4. Just above elbow for rear shoulder raise
5. Upper knee for hip raise
6. Rear lower-leg for hip swing back

Need to be able to set a threshold for the sensors for each position’s EoCL (Edge of comfort level). If the threshold is not triggered, the joint remains un-actuated and under the pilot’s power. Or perhaps some variant of this method that proportionately increases the actuator power with the amount of force registered by the sensor. This selective passivity will allow for a greater amount of power conservation and employ more natural stored energy release for things like the Contra-Postal walk that kind of feeds itself energy via the spinal torsions, arm swing and hip swing.

Phillip

Please reply to: phillipv at nb.sympatico.ca]]> guest E-mail Bag Sun, 07 Dec 2008 16:55:03 -0800 http://www.reconnsworld.com/forum/read.php?37,512,512#msg-512 HELP ME PLSSSS....... (no replies) http://www.reconnsworld.com/forum/read.php?37,512,512#msg-512
can you give me a schematic diagram for a transistor based power supply AC to DC

output voltage:

2.5
5.5
8
10
12

thx...i need di as soon as possible...

email me at thugsterz_15@yahoo.com]]> guest E-mail Bag Tue, 19 Aug 2008 05:46:44 -0700 http://www.reconnsworld.com/forum/read.php?26,511,511#msg-511 HELP ME PLSSSS...... (no replies) http://www.reconnsworld.com/forum/read.php?26,511,511#msg-511
can you give me a schematic diagram for a transistor based power supply AC to DC

output voltage:

2.5
5.5
8
10
12

thx...i need dis as soon as possible...

email me at thugsterz_15@yahoo.com]]> guest Comments, Suggestions, Conversation Tue, 19 Aug 2008 05:43:59 -0700 http://www.reconnsworld.com/forum/read.php?26,510,510#msg-510 HELP ME PLSSSS...... (no replies) http://www.reconnsworld.com/forum/read.php?26,510,510#msg-510
can you give me a schematic diagram for a transistor based power supply AC to DC

output voltage:

2.5
5.5
8
10
12

thx...i need di as soon as possible...

email me at thugsterz_15@yahoo.com]]> guest Comments, Suggestions, Conversation Tue, 19 Aug 2008 05:43:49 -0700 http://www.reconnsworld.com/forum/read.php?26,509,509#msg-509 HELP ME PLSSSS....... (no replies) http://www.reconnsworld.com/forum/read.php?26,509,509#msg-509
can you give me a schematic diagram for a transistor based power supply AC to DC

output voltage:

2.5
5.5
8
10
12

thx...i need di as soon as possible...

email me at thugsterz_15@yahoo.com]]> guest Comments, Suggestions, Conversation Tue, 19 Aug 2008 05:40:43 -0700 http://www.reconnsworld.com/forum/read.php?26,508,508#msg-508 TRANSISTOR BASED POWER SUPPLY AC to DC (no replies) http://www.reconnsworld.com/forum/read.php?26,508,508#msg-508
can you give me a schematic diagram for a transistor based power supply AC to DC

output voltage:

2.5
5.5
8
10
12

thx...i need di as soon as possible...

email me at thugsterz_15@yahoo.com]]> guest Comments, Suggestions, Conversation Tue, 19 Aug 2008 05:39:06 -0700 http://www.reconnsworld.com/forum/read.php?26,507,507#msg-507 TRANSISTOR BASED POWER SUPPLY AC to DC (no replies) http://www.reconnsworld.com/forum/read.php?26,507,507#msg-507
can you give me a schematic diagram for a transistor based power supply AC to DC

output voltage:

2.5
5.5
8
10
12

thx...i need di as soon as possible...]]> guest Comments, Suggestions, Conversation Tue, 19 Aug 2008 05:38:19 -0700 http://www.reconnsworld.com/forum/read.php?26,506,506#msg-506 High frequency ring tone detector (no replies) http://www.reconnsworld.com/forum/read.php?26,506,506#msg-506 guest Comments, Suggestions, Conversation Thu, 17 Jul 2008 13:03:12 -0700 http://www.reconnsworld.com/forum/read.php?12,501,501#msg-501 A circuit to generate between 16 khz and 20 Khz Ultrasound (no replies) http://www.reconnsworld.com/forum/read.php?12,501,501#msg-501
I'm new at this fórum. I'm not good at electronics, but I like to make some gadgets at home.

I'm trying to find, in the WEB, some circuits to produce 16 Khz Ultrasound. I'm planning to make a gadget with it.

I, only, found a circuit to produce 40 to 50 Khz Ultrasound, but I think it is very high for my project.

Can anyone help to find it?

Thanks. Sorry about my english. It isn't very good.

Pedro]]> pedro Sound Generators Tue, 22 Jan 2008 15:15:55 -0800 http://www.reconnsworld.com/forum/read.php?10,500,500#msg-500 what amps RMS (no replies) http://www.reconnsworld.com/forum/read.php?10,500,500#msg-500 Thanks]]> mercy Amplifiers Thu, 25 Oct 2007 18:36:01 -0700 http://www.reconnsworld.com/forum/read.php?10,496,496#msg-496 Simple Tube Amp (no replies) http://www.reconnsworld.com/forum/read.php?10,496,496#msg-496 I'm looking for a schematic for a simple tube amp that would run on DC/batteries... I was hoping to use some tubes I already have such as a couple of 1S4's . Can anyone help?

Bill
ag2217@yahoo.com]]> ag1722 Amplifiers Sat, 31 Mar 2007 21:42:28 -0700 http://www.reconnsworld.com/forum/read.php?10,494,494#msg-494 8 Watt amp problems (no replies) http://www.reconnsworld.com/forum/read.php?10,494,494#msg-494 www.aaroncake.net]

However, I could not locate an LM383 or an ECG1232 that the parts list showed as an alternate amp IC. I read somewhere on the net (can't remember where) that an NTE7143 20W IC can be used in place of the others. I built the amp, but can't get it to work. It comes on, but all I get out of the speaker is a hum. The IC gets pretty hot as well even with a heatsink. I shut it down because I'm afraid of burning up the IC. Did I use the wrong IC? What other IC's can I use in place of the others? I added the 0.02 uF cap and a 2 Ohm resistor in the circuit per what the the website listed above. Anyone got any ideas?]]> grandpaslincoln Amplifiers Sun, 18 Feb 2007 16:37:59 -0800 http://www.reconnsworld.com/forum/read.php?13,493,493#msg-493 12V power supply for amp (no replies) http://www.reconnsworld.com/forum/read.php?13,493,493#msg-493

Thanks,
Jon]]> grandpaslincoln Power Supplies Sun, 18 Feb 2007 16:30:45 -0800 http://www.reconnsworld.com/forum/read.php?18,490,490#msg-490 Can you help? (no replies) http://www.reconnsworld.com/forum/read.php?18,490,490#msg-490 I am not an electronics expert, so may I ask your advice/ pick your brains, and maybe even get some "build it yourself" diagrams.

My problem is this:

In the UK, some railway lines are layed using steel sleepers (the bits the lines sit on) See: [www.pandrol.com]

The sleepers are insulated from the rails by insulating pads (approx. 10mm thick).
To detect the passage of trains, most use a small (2-6 Volts) DC voltage fed down one rail, through a relay coil and back down the other rail. The trains axles short out the rails, the relay coil loses voltage, and an indication is sent back to the signalling centre.
Some track circuts use a frequency to achieve this, common ones are, 1700Hz, 2000Hz, 2300Hz, and 2600Hz
Some track circuits use a tuned "reed" at the frequencies from 363Hz-423Hz, going up in 3Hz steps.
In all the different track circuits, the train axles short out the rails, dropping the relay.

When we've been on a relaying job, sometimes a steel sleeper(s) get the insulating pads left out, shorting out the rails. The signalling system thinks that there is a train sitting there, and those gallant chaps from the Signalling Dept. have to go and find the offending sleeper(s).

What I was thinking was, rather than use a voltage to find the location of the short circuit, as the voltage is too supceptable to the many of the variables, particularly the length of track circuits (from 20 to 1000 meters), I could use a frequency.

I would need a transmiter putting out enough power to go 1000 meters.
My idea would be to use both the rails as the arial, and send the transmitted signal down the whole length of the track circuit. The distance between the rails in the UK is 1432mm (4foot 8 inches), so I need the receiver to be sensative, but directional, as I will be pointing it at the sleepers, from a max. height of about six inches. My idea being that where the steel sleeper is in contact with the rail, it will become part of the transmitting arial, be detected by the receiver, and BINGO!, we've found the fault. A lot quicker than the current method of clearing every sleeper of stone and physicaly checking. (Sleeper spacing about 750mm, thats 1250 sleepers checked both sides for a 1000 metre relay!)

Limitations are that with the frequencies in use on the railways, and their harmonics, namely as mentioned above,the 50Hz traction current frequency, and the following TPWS frequencies (a train protection system), that uses:

64.25, 64.75, 65.25, 65.75, 66.25, 66.75 all kHz

It's also got to be small enough to be "one-person" portable (esp. the receiver!)

Thanks in advance for your thoughts ideas,

Chris]]> Chris Wink Radio Wed, 27 Sep 2006 12:59:02 -0700 http://www.reconnsworld.com/forum/read.php?26,487,487#msg-487 metal detectors here... (no replies) http://www.reconnsworld.com/forum/read.php?26,487,487#msg-487 sonar Comments, Suggestions, Conversation Wed, 20 Sep 2006 00:27:25 -0700 http://www.reconnsworld.com/forum/read.php?21,459,459#msg-459 UHF transmitter (1 reply) http://www.reconnsworld.com/forum/read.php?21,459,459#msg-459 I have a problem with my transmitter UHF I can't to add a sound in the transmitter what can I do? please help me if u have a audio transmitter around 247.25 Mhz, the video work good but the audio is my problem.
Thanks ti answer me
see u]]> Nia RF transmitters Fri, 18 Aug 2006 10:07:25 -0700 http://www.reconnsworld.com/forum/read.php?37,453,453#msg-453 ic preamp circuit & ipod (no replies) http://www.reconnsworld.com/forum/read.php?37,453,453#msg-453 -----------------
from ehiunno
Quote

I see the preamp is labeled for use with an electret microphone, but the application im working on requires the amplication of a low-level source(namely, an ipod) a small amount as the headphone out doesnt put out at line-level. Could i use this pre-amp in this application?

It aslo seems to me that the circuit might create a high pass-filter with a cutoff frequency well above where i would want it (created by C1 and R2) but i may be missing something or doing incorrect math as i couldnt imagine why you would want to filter out such high fequencies for a mic. Do you have the theoretical cutoffs of any of the filters in the preamp? I need something that will amplify the entire audio spectrum.

thanks a lot,
Brielin
---------------------
my response:
Quote

hey, sorry for the delay in getting back to you.

well, firstly the forum you emailed me through is deprecated (i need to take it down and fwd. all traffic to the new forum at [www.reconnsworld.com])

looking at the circuit, I'm not sure which section you think will create a high-pass filter.. (r1 & c1? r5 & c2?)

meanwhile this schematic looks very similar to a reference audio amplifier design that national semiconductor has on their website:
[webench.national.com]

so i imagine it works well. the main difference seems to be the r1 supplying voltage to the electret microphone, which in your case you don't need. in your case you would need to remove r1 and feed directly into the pin on c1.

wikipedia (http://en.wikipedia.org/wiki/Line_level) has line voltage at about 1.228vrms which would be 1.228v*(2*sqrt(2)) = 3.47v peak-to-peak
audio electronics really isn't my thing, and I can't seem to find a definitive source about 'what voltage does the ipod run the headphones', is it larger/smaller than 3.47?

meanwhile, if you're interested in a circuit that should definitely meet your specs you should check out national semi's website. they have a tool called 'my webench' which allows you to design circuits, on the website, and simulate them to make sure they operate to your spec.

check it out at
[www.national.com]

i followed the 'audio' link under the 'design' section. meanwhile they do have samples available for some of their chips, so that may help your project out.

let me know if that works for you -- also i'd appreciate if you gave me your opinion of the new forum vs. old forum

thanks,
andrew
]]> andrew E-mail Bag Tue, 15 Aug 2006 17:59:45 -0700 http://www.reconnsworld.com/forum/read.php?26,448,448#msg-448 testing smilies (2 replies) http://www.reconnsworld.com/forum/read.php?26,448,448#msg-448

:smile: :sad: :biggrin: :tounge:]]> andrew Comments, Suggestions, Conversation Tue, 01 Aug 2006 17:17:45 -0700 http://www.reconnsworld.com/forum/read.php?26,446,446#msg-446 Power to the Circuit (1 reply) http://www.reconnsworld.com/forum/read.php?26,446,446#msg-446 So Im trying to build a simple 2 channel mixer with gain and adjustable bass and treble. That i pretty much now how to do. Schematics and stuff about these are quite easy to find. But what I dont know is how to power the OA-s. Im using TL072-s and no matter what I do, I still get noise in the output. Noise is kind of like 50Hz hum but the music is distorted also. I tried to add capacitors and change the feedback amount etc but still nothing. Im trying to amplify the signal from Line output from my Numark TTX1 turntables (they have turntable preamps built in).
If anyone can draw a simple schematic how to power the TL072s, please post it here. Many thanks to those who reply.]]> mote Comments, Suggestions, Conversation Tue, 15 Aug 2006 18:11:01 -0700 http://www.reconnsworld.com/forum/read.php?26,434,434#msg-434 200w valve amps (1 reply) http://www.reconnsworld.com/forum/read.php?26,434,434#msg-434
I'd like to mention that this is a wonderful site that you have here,and that I will be posting some schematics on R.F transmission equipment on your site for use,later on when my research has been completed.

I just want to find out if anybody has perhaps come up with some kit design for a really strong valve High Fidelity amplifier, say 200 watts or more? I would really like to know as I would like to build myself a good,strong amplifier and believe that valves are the best way of amplification for audio use.

Kind regards!!]]> boetie Comments, Suggestions, Conversation Tue, 15 Aug 2006 18:12:38 -0700 http://www.reconnsworld.com/forum/read.php?24,423,423#msg-423 Reducing Voltage (1 reply) http://www.reconnsworld.com/forum/read.php?24,423,423#msg-423 What I want to do is add a component between the connectors of the battery pack and the toy that will limit the volts to 7.2v regardless of the power pack voltage.
This way if I can use a 9.6v pack or higher and the component will step the voltage down to what the toy requires. I included an rough schematic to show the toy and power pack. the Connector is 2 prong]]> nomadsworld Other Wed, 12 Jul 2006 20:38:50 -0700 http://www.reconnsworld.com/forum/read.php?8,420,420#msg-420 Electronic fly swatter help (1 reply) http://www.reconnsworld.com/forum/read.php?8,420,420#msg-420 Brent Miscellaneous Sun, 18 Jun 2006 14:27:31 -0700 http://www.reconnsworld.com/forum/read.php?24,419,419#msg-419 Under voltage and Over voltage for 120v AC system (no replies) http://www.reconnsworld.com/forum/read.php?24,419,419#msg-419 shaft47 Other Sun, 19 Mar 2006 15:34:00 -0800 http://www.reconnsworld.com/forum/read.php?8,418,418#msg-418 Mosquitoes Repellant!!! (no replies) http://www.reconnsworld.com/forum/read.php?8,418,418#msg-418 it's said that this circuit repell female mosquitoes, i don't know, i need your feed back plz.

]]> golden-heart Miscellaneous Mon, 27 Feb 2006 02:42:54 -0800 http://www.reconnsworld.com/forum/read.php?21,414,414#msg-414 Simple RF transmitter - how to test (no replies) http://www.reconnsworld.com/forum/read.php?21,414,414#msg-414 lynn RF transmitters Thu, 09 Feb 2006 06:40:40 -0800 http://www.reconnsworld.com/forum/read.php?18,413,413#msg-413 Modification in FM transmitter (2 replies) http://www.reconnsworld.com/forum/read.php?18,413,413#msg-413
I have a miniature, low-power FM transmitter (which can be used as a spy-tool). It transmits sound which have been received by little electret microphone included "on-board". Now i want to join this transmitter with e.g. computer or mp3-player, to transmit audio signal from line-in cable...

Here is the scheme: [rapidshare.de]

What do i have to change in this transmitter? How and where to plug the audio-signal from sound-card or mp3-player? Plz help me, i cannot find solution ANYWHERE in polish internet!!! Thx in advance ;)

Scheme here too:]]> Magz100 Radio Sun, 26 Mar 2006 18:14:58 -0800